cc: switch to new WebLayerTreeViewClient API for requesting font atlas

cc/test/layer_tree_test_common.cc

Index: cc/test/layer_tree_test_common.cc
diff --git a/cc/test/layer_tree_test_common.cc b/cc/test/layer_tree_test_common.cc
index 8be9cf95a54714ff710a6c5d4d30a04189c8cbd8..f24d8e687e6be4bad8fb0f8fbe5ea12924edb821 100644
--- a/cc/test/layer_tree_test_common.cc
+++ b/cc/test/layer_tree_test_common.cc
@@ -7,6 +7,7 @@
 #include "base/stl_util.h"
 #include "cc/active_animation.h"
 #include "cc/content_layer.h"
+#include "cc/font_atlas.h"
 #include "cc/input_handler.h"
 #include "cc/layer.h"
 #include "cc/layer_animation_controller.h"
@@ -25,6 +26,7 @@
 #include <public/WebFilterOperation.h>
 #include <public/WebFilterOperations.h>
 
+using cc::FontAtlas;
 using cc::InputHandler;
 using cc::Layer;
 using cc::LayerTreeHostImplClient;
@@ -263,6 +265,11 @@ public:
         m_testHooks->scheduleComposite();
     }
 
+    virtual scoped_ptr<FontAtlas> createFontAtlas() OVERRIDE
+    {
+        return scoped_ptr<FontAtlas>();
+    }
+
 private:
     explicit ThreadedMockLayerTreeHostClient(TestHooks* testHooks) : m_testHooks(testHooks) { }